Chapter 4 of this report highlights the research and operational benefits of mission extension. Cost refers to the cost of mission operations, controlled reentry, and science data processing. Risk refers to the risk to lives and property from spacecraft debris in the event of uncontrolled reentry.

COST

The mission cost of TRMM to date is at least $750 million.2 Even if NASA terminates TRMM in December 2004, there will be more than $13 million in additional costs for operating the satellite until 2007 when controlled reentry would occur.3 There is no question that NASA and the Japan Aerospace Exploration Agency have invested large sums in TRMM beyond the spacecraft’s original planned five-year life and they should be commended for this.

The cost of mission extension beyond 2004 is illustrated in Table 2-1. These calculations are for extension of operations to November 2005 and controlled reentry in the first quarter of 2008 after roughly two years of driftdown. NASA has approached other agencies for their help in supporting the cost of extending the mission beyond 2004 but without success to date.4 Current NASA policy regarding mission extensions puts the burden on research programs to underwrite costs incurred by NASA.5 The current NASA precipitation research budget is around $16 million per year.

The key budget number in Table 2-1 is the combined cost of mission operations and controlled reentry in fiscal year 2005, that is, $4.3 million. This is the approximate additional cost of operating TRMM until November 2005 instead of December 2004.6 NASA separates the total cost into three components: mission operations, controlled reentry, and science data processing. The first and last of these are approximately equal and collectively contribute 90 percent or more to the overall annual cost in Table 2-1. Science data processing includes TRMM-related, Global Precipitation Measurement (GPM)-related, and general precipitation data processing costs and is not uniquely tied to the TRMM mis-

2

Lawler (2004) quotes a figure of $600 million. According to Robert Adler, NASA, this is probably an approximate cost of building and launching TRMM. By considering cost of data processing for 10 years and science team support for 7 years, the estimated cost increases to approximately $750 million. This is still a minimum estimate, since the full cost from the Japanese contribution to TRMM is not included.

3

Costs are drawn from data presented to the committee by Jack Kaye, NASA. There is roughly a two-year window after termination when the satellite drifts to a lower orbit in preparation for reentry.

4

Jack Kaye, NASA, indicated this in his presentation to the committee at the November 8 workshop.

5

Ibid. Mary Cleave, NASA, confirmed this policy at the November 8 workshop.

6

This estimate is in addition to the roughly $13 million (mentioned above) that would be incurred during the three fiscal years after termination while the spacecraft drifted down in preparation for controlled reentry.



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